The purpose of this study is to characterize the lung inflammatory and immune responses to isocyanates in subjects with known isocyanate asthma and to develop an in vitro marker to assess sensitization to isocyanates. Sixty subjects in autobody shops have undergone intensive field assessment, and six suspect isocyanate asthma patients will be invited to undergo this protocol. In addition, 10 exposed controls will also participate in the search for immune markers of exposure sensitization and overt disease. At the same time another 100 workers will undergo the surveillance tests in the next year.